Dosage tracking apparatus, dosage tracking system, and related methods of use

Abstract

An apparatus for tracking an amount of dispensed fluid, a system for fluid injection including the apparatus, and related methods of use are described. In an embodiment, the apparatus includes a dosage meter shaped to couple with a leadscrew and a cartridge containing a fluid for injection, and configured to track fluid injection. In an embodiment, the dosage meter includes an index wheel including a plurality of teeth, wherein the index wheel is shaped to position coaxially with a major axis of the leadscrew and to receive rotational motion from the leadscrew; and a cantilevered protrusion positioned to deflect due to contact with the plurality of teeth as the index wheel rotates coaxially with the leadscrew inducing a strain in the cantilevered protrusion, wherein the dosage meter outputs a signal indicative of the strain.

What is claimed is: 
     
         1 . An apparatus for measuring an amount of a dispensed fluid, the apparatus comprising:
 a dosage meter shaped to couple with a leadscrew and a cartridge containing a fluid for injection, the dosage meter comprising:
 an index wheel including a plurality of teeth, wherein the index wheel is shaped to position coaxially with a major axis of the leadscrew and to receive rotational motion from the leadscrew; and 
 a cantilevered protrusion positioned to deflect due to contact with the plurality of teeth as the index wheel rotates coaxially with the leadscrew; and 
   a leadscrew extender positioned to be in contact at a first end of the leadscrew extender with a portion of the cartridge and at a second end of the leadscrew extender with an end of the leadscrew.   
     
     
         2 . The apparatus of  claim 1 , wherein the leadscrew extender is shaped to receive motion of the leadscrew along the major axis of the leadscrew. 
     
     
         3 . The apparatus of  claim 1 , wherein the leadscrew extender is shaped to transfer the rotational motion of the leadscrew to the index wheel. 
     
     
         4 . The apparatus of  claim 1 , wherein the plurality of teeth extend radially from a major axis of the index wheel. 
     
     
         5 . The apparatus of  claim 4 , wherein the cantilevered protrusion is positioned to deflect radially from the major axis of the index wheel. 
     
     
         6 . The apparatus of  claim 1 , wherein the dosage meter includes a strain sensor disposed on the cantilevered protrusion to generate a signal indicative of strain induced by deflection of the cantilevered protrusion. 
     
     
         7 . The apparatus of  claim 6 , wherein the strain sensor is positioned on a circuit board. 
     
     
         8 . The apparatus of  claim 1 , wherein the dosage meter includes a bracket shaped and positioned to place the cantilevered protrusion in contact with one of the plurality of teeth. 
     
     
         9 . The apparatus of  claim 8 , wherein the bracket includes a columnar portion shaped to receive a portion of the leadscrew and shaped to position the index wheel coaxially with the major axis of the leadscrew. 
     
     
         10 . The apparatus of  claim 9 , wherein the bracket does not receive the rotational motion, and wherein the cantilevered protrusion remains static relative to the rotational motion. 
     
     
         11 . The apparatus of  claim 1 , further comprising:
 a housing shaped to accept the cartridge containing the fluid; and   a fluid injector including the leadscrew that produces rotational motion about the leadscrew major axis when the apparatus dispenses the fluid from the cartridge.   
     
     
         12 . The apparatus of  claim 1 , wherein the dosage meter outputs a signal indicative of deflection of the cantilevered protrusion, the apparatus further comprising a controller operatively coupled to the dosage meter and including logic that when executed by the controller causes the apparatus to perform operations including:
 tracking the signal output from the dosage meter.   
     
     
         13 . The apparatus of  claim 12 , wherein the controller further includes logic that when executed by the controller causes the apparatus to perform operations including:
 registering the signal as an injection event of the dispensed fluid; and   calculating a number of injection events of the fluid.   
     
     
         14 . The apparatus of  claim 12 , wherein the controller further includes logic that when executed by the controller causes the apparatus to perform operations including:
 calculating a quantity of the fluid dispensed based on the signal.   
     
     
         15 . The apparatus of  claim 13 , further comprising:
 a power source coupled to the controller; and   a transceiver coupled to the controller to send and receive data, wherein the controller further includes logic that when executed by the controller causes the apparatus to perform operations including:
 instructing the transceiver to send the data to an external device, wherein the data includes information indicative of the number of injection events. 
   
     
     
         16 . A method of measuring a quantity of fluid dispensed from an apparatus comprising:
 rotating an index wheel of the apparatus about a major axis of a leadscrew coaxially received by the index wheel as fluid is dispensed to deflect a cantilevered protrusion disposed to engage the index wheel as the index wheel rotates;   generating a signal indicative of the deflection of the cantilevered protrusion; and   tracking the signal indicative to determine the quantity of the fluid dispensed.   
     
     
         17 . The method of  claim 16 , wherein generating the signal includes:
 deflecting the cantilevered protrusion with a tooth extending radially from a major axis of the index wheel, wherein the cantilevered protrusion deflects radially from the major axis of the index wheel in response to the tooth pressing against the cantilevered protrusion; and   generating with a strain sensor disposed on the cantilevered protrusion and coupled to a controller the signal.   
     
     
         18 . The method of  claim 16 , wherein tracking the signal includes storing the signal in memory disposed in the apparatus using a controller coupled to receive the signal. 
     
     
         19 . The method of  claim 16 , further comprising registering the signal as an injection event of the fluid and calculating a quantity of the fluid dispensed based on the signal. 
     
     
         20 . The method of  claim 19 , further comprising transmitting data, representative of the signal, to a processing device that is distinct from the apparatus, wherein the processing device calculates the quantity of fluid dispensed.